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[213.44.141.166]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-432da27f4f8sm209297365e9.18.2024.11.19.14.51.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Nov 2024 14:51:54 -0800 (PST) From: Valentin Schneider To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, x86@kernel.org, rcu@vger.kernel.org, linux-kselftest@vger.kernel.org, Masami Hiramatsu , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Josh Poimboeuf , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , Juri Lelli , Marcelo Tosatti , Yair Podemsky , Daniel Wagner , Petr Tesarik Subject: Re: [RFC PATCH v3 00/15] context_tracking,x86: Defer some IPIs until a user->kernel transition In-Reply-To: <20241119114556.0949b562@gandalf.local.home> References: <20241119153502.41361-1-vschneid@redhat.com> <20241119114556.0949b562@gandalf.local.home> Date: Tue, 19 Nov 2024 23:51:52 +0100 Message-ID: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: r1OPz-fOz4gK-jzQVEQVTVvC4kXlq48kYo5gRZa1osE_1732056715 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: CECC91A000C X-Stat-Signature: jcpbs7g4aaam1z9fmuzwknq7y3ibpwjp X-HE-Tag: 1732056654-698440 X-HE-Meta: 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 T6VOBjP/ oXBWbFzeCWU8oRwHIuwsgvXQ58yN5iZE4GILBvsDuLkWD5tc1a1BHbtZYLq+QoNvKAT2R63ImOiddFXi8lG4gZjyBxHLMtWIonyKF9XRrAZNWwGiHFudhvnjJL7zbHtYR7U5fu62mYTZ1VRrT5xoGZCtbay1dOCClxBPMGRQag+KZ2IQToMpceeMKVdSKIWMZyrNI5e0NapmWrddAh8/lHuANlnB2DIC8TF8ixjNlEhVsmRw79vIQh2kJmGV7dguLaKBkdd6K5cLnGpFHXPWpoqUekloEWCd3Luh9K3DYZSxan4ScHqw0KOS/+EBZr1jIzN1QXGJm4hJCbeKGgUU9t+S/5JBdZIcjqMKD9V+BCSO7jFGycqQJm4vEbHIh/t3/6ZukhF1sqfQa0/jQRvfjs2NrYfW6XoLPTuGrPgjnmhxYdg6LIyj84wu3RJ/v9e8WJOpf X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 19/11/24 11:45, Steven Rostedt wrote: > On Tue, 19 Nov 2024 16:34:47 +0100 > Valentin Schneider wrote: > >> Context >> ======= >> >> We've observed within Red Hat that isolated, NOHZ_FULL CPUs running a >> pure-userspace application get regularly interrupted by IPIs sent from >> housekeeping CPUs. Those IPIs are caused by activity on the housekeeping CPUs >> leading to various on_each_cpu() calls, e.g.: > > FYI, > > Sending a patch series at the start of the merge window is likely going to > get ignored. > > Care to resend after rc1 is released? Or at least ping about it. > Heh, I was so far down "stop rewriting changelogs for the Nth time, get it in a decent shape and send it out" that I forgot about this "small little detail". Thanks for the reminder.